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(guile.info)Random

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Random Number Generation
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 - primitive: copy-random-state [state]
     Return a copy of the random state STATE.

 - primitive: random n [state]
     Return a number in [0,N).  Accepts a positive integer or real n
     and returns a number of the same type between zero (inclusive) and
     N (exclusive). The values returned have a uniform distribution.
     The optional argument STATE must be of the type produced by
     `seed->random-state'. It defaults to the value of the variable
     *random-state*. This object is used to maintain the state of the
     pseudo-random-number generator and is altered as a side effect of
     the random operation.

 - primitive: random:exp [state]
     Returns an inexact real in an exponential distribution with mean 1.
     For an exponential distribution with mean u use (* u (random:exp)).

 - primitive: random:hollow-sphere! v [state]
     Fills vect with inexact real random numbers the sum of whose
     squares is equal to 1.0.  Thinking of vect as coordinates in space
     of dimension n = (vector-length vect), the coordinates are
     uniformly distributed over the surface of the unit n-shere.

 - primitive: random:normal [state]
     Returns an inexact real in a normal distribution.  The
     distribution used has mean 0 and standard deviation 1.  For a
     normal distribution with mean m and standard deviation d use `(+ m
     (* d (random:normal)))'.

 - primitive: random:normal-vector! v [state]
     Fills vect with inexact real random numbers that are independent
     and standard normally distributed (i.e., with mean 0 and variance
     1).

 - primitive: random:solid-sphere! v [state]
     Fills vect with inexact real random numbers the sum of whose
     squares is less than 1.0.  Thinking of vect as coordinates in
     space of dimension n = (vector-length vect), the coordinates are
     uniformly distributed within the unit n-shere.  The sum of the
     squares of the numbers is returned.

 - primitive: random:uniform [state]
     Returns a uniformly distributed inexact real random number in
     [0,1).

 - primitive: seed->random-state seed
     Return a new random state using SEED.